A 20-year experience using sodium tetradecyl sulfate (Sotradecol, Elkins-Sinn, Inc., Cherry Hill, NJ) for the injection treatment of spider telangiectasias is reviewed. Of 1426 legs injected, 882 were treated with a 1%-solution injected directly into the spider veins, and 264 were injected directly with a 1/3%-solution. With the 1/3%-solution, the remaining 280 legs had the blue veins feeding the spider telangiectasias injected rather than the spider itself. When injected directly into the spider veins, the lesser concentration gave fewer ulcerations and less pigmentation, but equal treatment results. Injecting the subcutaneous feeder veins appears to provide more permanent clearing of the lesions with fewer recurrences and no side effects. No allergic or other major complications occurred with the injection treatments.